20 lines
594 B
C++
20 lines
594 B
C++
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#include <iostream>
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#include <Eigen/SVD>
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using namespace Eigen;
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using namespace std;
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float inv_cond(const Ref<const MatrixXf>& a)
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{
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const VectorXf sing_vals = a.jacobiSvd().singularValues();
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return sing_vals(sing_vals.size()-1) / sing_vals(0);
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}
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int main()
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{
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Matrix4f m = Matrix4f::Random();
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cout << "matrix m:" << endl << m << endl << endl;
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cout << "inv_cond(m): " << inv_cond(m) << endl;
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cout << "inv_cond(m(1:3,1:3)): " << inv_cond(m.topLeftCorner(3,3)) << endl;
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cout << "inv_cond(m+I): " << inv_cond(m+Matrix4f::Identity()) << endl;
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}
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